Time delay control device



1955 s. J. MlKINA ETAL 3,213,333

TIME DELAY CONTROL DEVICE Filed June 28, 1963 3 Sheets-Sheet 2 Fig.3.

1965 s. J. MIKINA ETAL TIME DELAY CONTROL DEVICE 3 Sheets-Sheet 3 Filed June 28, 1963 Fig 7 &

I I o P w m s m 5 I \Q United States Patent 3,213,333 TIME DELAY CUNTRUL DEVICE tanley J. Milrina, Penn Hills, and Merrideth D. Wilson,

Monroeville, lia., assignors to Westinghouse Electrie Corporation, Pittsburgh, Pa., a corporation of Pennsylvania lFiled June 28, 1963, Ser. No. 291,565 22 Claims. (Cl. 317178) This invention relates generally to control devices, and more particularly to time delay mechanisms and to electrical control structures of the type comprising a time delay mechanism.

In the control art, the flow of fluid or air through an orifice from or into a varying volume is often utilized as the means for providing a time interval between an actuation and a response to the actuation. In the prior art, time delays have often been effected by changing the volume of a deformable chamber against the force of a biasing means, and then letting the charged biasing means restore the chamber to its initial volume by forcing air through a tapered-needle type valve that connects the chamber to another atmosphere. The time delay has been varied by a screw-type adjustment of the needle relative to a valve seat to vary the dimension of the orifice through which the fluid flows.

There are basic disadvantages to this variable-orifice type of timing apparatus. A plotted curve of the time delay versus the needle valve travel is non-linear. The time delay is substantially proportional to the inverse first power of the needle displacement from its seat. Hence, for the longer delays obtained with the needle valve nearly closed, a small amount of needle displacement will result in a comparatively large change in the time delay, thus making the needle valve adjustment more critical. At the opposite end of the scale, when the needle is far off its seat for short time delays, a comparatively large amount of needle travel is required to effect a change in the time delay. Thus, at each time delay setting, a different rate of change of time delay per unit of needle valve adjusting-screw rotation exists so that it is relatively difficult to determine how far to move the adjusting screw to effect a given change in the time delay to fit a particular operational requirement. Moreover, for a given time delay, the orifice opening is relatively small and hence relatively more vulnerable to a change of calibration as a result of dirt particles that may become lodged in the orifice. Furthermore, the annularshaped valve opening is extremely small when the device is adjusted for long time delays so that, in order to obtain calibration repeatedly under these conditions, very close manufacturing tolerances must be maintained on the needle valve surface, and on the mating valve seat.

Accordingly, an object of this invention is to provide an improved time delay mechanism that has a linear adjustment feature and that is less vulnerable, due to a relatively large orifice opening, to changes in calibration due to dirt particles that may become lodged in the orifice.

Another object of this invention is to provide an improved time delay mechanism having a novel type of adjustable fluid flow path.

A more general object of this invention is to provide an improved time delay mechanism.

Another object of this invention is to provide an improved electrical control structure that operates with a time delay.

Other objects of this invention will be explained fully hereinafter or will be apparent to those skilled in the art.

Reference is herein made to our copending patent ap- "ice plication Serial No. 174,818, filed February 21, 1962 and assigned to the assignee of the instant application.

This invention, both as to structure and operation, together with additional objects and advantages thereof, will be best understood from the following detailed description thereof when read in conjunction with the accompanying drawings.

In said drawings:

FIGURE 1 is a sectional view taken generally along the line I-I of FIG. 2 and illustrating a control device embodying principles of this invention;

FIG. 2 is a sectional view taken generally along the line IIII of FIG. 1;

FIG. 3 is an enlarged sectional view illustrating part of the time delay mechanism seen in FIGS. 1 and 2;

FIG. 4 is a plan view of one of the parts of the mechanism seen in FIG. 3;

FIG. 5 is a partial view, in section, illustrating another embodiment of the invention;

FIG. 6 is a partial View, in section, illustrating another embodiment of the invention;

FIG. 7 is a partial view, in section, illustrating another embodiment of the invention; and

FIG. 8 is a partial View, in section, illustrating still another embodiment of the invention.

Referring to the drawings, there is shown, in FIGS. 1 and 2, a control device 5 comprising a control structure 7 and a time delay mechanism or apparatus 9. The control structure 7 may be a contactor or relay, or other similar type of electromagnetic control structure. As is shown in the drawings, the control structure 7 is a relay that, except for the contact carrier structure that will be hereinafter specifically described, is of a type specifically described in the patent to Gustav Jakel, Patent No. 3,088,058, issued April 30, 1963. For this reason, only a brief description of the relay 7 is given herein.

The relay 7 comprises a housing comprising a base 13 and a cooperating cover 15 both of which are of molded insulating material. The base 13 and cover 15 are held firmly together as a unit by means of bolts (not shown) that are disposed at diagonal corners of the housing. The relay 7 is supported on a base plate 17 by suitable securing means. An E-shaped laminated main magnet or core member 19 is supported in the housing base 13. As is seen in FIG. 1, the legs of the E-shaped core member 19 extend upwardly. A magnetizing winding, or coil 21, is disposed on a suitable spool 23 of insulating material. The spool 23 and coil 21 are positioned over the middle leg of the E-shaped core member 19. Two terminals 25 (only one of which is seen in FIG. 2) are provided at diagonal corners of the relay 7 to enable connection of the coil 21 in an electrical circuit.

An E-shaped laminated armature member 2'7 is provided to cooperate with the core member 19. The armature member 27 is connected to a molded insulating outercontact carrier 29 by means of a pin 30, which pin 30 pivotally mounts the armature 27 on the contact carrier 29 so that the armature, within certain limits, has freedom of rotation in the plane of the paper as seen in FIG. 1.

The relay 7 comprises four pole units, each of which pole units comprises oppositely disposed stationary contact structures 31 (FIG. 1) that are supported on the upper housing part 15 by means of terminal screws 33. A stationary contact 35 is provided at the inner end of each of the stationary con-tact structures 31. In each pole unit a movable bridging contact member 37, having a contact 39 at each of the two opposite ends thereof, is provided to bridge the contacts 35. As is seen in FIG. 1, the contacts are shaped and disposed so that the contacts are normally closed when the solenoid coil 21 is in the upper denergized position. The bridging contact member 37 is adapted to move down to an open position in a manner to be hereinafter specifically described. The contact structure can, however, be constructed to be normally open. This is a matter of choice, and, depending upon particular control requirements, the relay can be adapted to have any combination of normally open and normally closed contacts in a manner well-known in the art.

The outer contact carrier 29, which is attached to and movable with the armature 27, controls and carries only the two bridging contact members 37 of the outer (FIG. 2) two pole units. The bridging contact members 37 for the two inside (FIG. 2) pole units are carried by a separate inner insulating contact carrier 41, which inner contact carrier is operable to control movement of the two inner bridging contact members 31 after a time delay in a manner to be hereinafter specifically described. Each of the bridging contact members 37 is disposed in an opening 42 (FIG. 2) in the associated contact carrier and is held in position by means of a spring 43 that also provides contact pressure when the contacts are in the closed position.

The time delay mechanism or apparatus 9 comprises an insulating base member 47 supported on a pair of brackets 49 that are secured to the relay 7 by means of bolts 51. The wall of the time delay apparatus 9 comprises a cylinder 53 that is secured to the base member 47. An annular member 55 is suitably secured to another annular member 56, which members are secured together by means of screws 57 (FIG. 2) that pass through an annular member 59 and the member 56 to engage in tapped openings in the member 55. A filter member 61 (FIG. 2) is supported between the members 59 and 53, 56. The members 59, 61, 55 and 56, which are all secured together, are supported on the cylinder 53 by means of suitable screws (not shown) that attach the member 55 to the cylinder 53. An adjusting structure 69 is supported on the block 56 in a manner to be hereinafter specifically described.

The time delay mechanism 9 also comprises a pushrod structure 71 and a bellows member 73 having a valveseat portion 74. The push-rod structure 71 comprises a lower rod portion 75, a shoulder portion 77, a valve 79 and an upper rod portion 81. When the armature 27 is in the open and upper position seen in FIGS. 1 and 2, the push-rod structure 71 rests on, but is not attached to, the top of the armature 27. A spring 83 disposed within the bellows valve chamber, engages the top of the valve 79 to bias the push-rod structure 71 into engagement with the armature 27. A spring 85 that is provided outside of the bellows valve chamber, and that is weaker than the spring 83, is provided to return the bellows valve 7.3 tothe compressed condition seen in FIGS. 1 and 2 after a time delay operation has occurred. Two springs 87 (FIG. 1) bias the inner contact carrier 41 downward, which movement is restricted by engagement of the contact carrier 41 with two bell-crank latches 89. The bellcrank latches 89 are biased to the latching position seen in FIG. 2 by means of torsion springs (not shown). The bell-crank type latches 39 are pivotally supported on the brackets 4-9 by means of pivot pins 91.

The bellows valve 73 is secured to the block 55 by means of a ring-shaped plate 93 that is secured to the block 55 by means of screws (not shown).

As is best seen in FIG. 3, there are three chambers within the time delay apparatus 9. These chambers comprise a lower chamber 95, an upper chamber 97 and a bellows chamber 99. The filter 61 permits air to filter into the chambers through a passage 101. The lower chamber 95 is connected to the upper chamber 97 through the passage 101 and a passage 103. The bellows chamber 99 is connected to the upper chamber 97 through two passages 105, a passage 107 in the block 55, a central opening or passage 109 in a grooved rigid plate 111,

through an adjustable spiral fluid flow path that com prises a spiral groove 113 (FIG. 4) leading from the passage 109. The working length of the groove 113 is the length that is covered at any particular time by the generally smooth surface 115 of a resilient adjusting member 117. The adjusting member 117 is suitably secured to a plate 119 that has a stem portion 121 that is guided; but not rigidly secured in an opening in a threaded adjusting member 123. A handle 125 is secured to the adjusting member 123 by means of a bolt 127. As is seen in FIG. 4, the plate 111 is a generally flat disc having the groove 113 formed spirally on the generally even flat face of the plate 111. The member 117 is a resilient member of rubber or other suitable resilient material.

A sealing O-ring is secured to the member 56 by means of a plate 131 that is held in place by means of screws 132.

The operation of the control device 5 is as follows:

As is seen in FIGS. 1 and 2, the control device 5 is shown with the coil 21 deenergized and the contacts 35, 39 of all of the four pole units in the normally closed position. In operation, when the coil 21 is energized, the armature 27 is attracted to move down to engage the core member 19. This movement of the armature 27 carries the outer contact carrier 29 and the two bridging contact members 37 for the two outer (FIG. 2) pole units downward to open the contacts 35, 39 for the two outer pole units. The inner contact carrier 41 remains in the upper position seen in FIGS. 1 and 2 because it is latched there by the bell-crank type latches 89. When the armature 27 moves downward, it moves away from the push rod structure 71 whereupon the spring 83, which is stronger than the spring 85, biases the valve 79 to force the push-rod structure '71 downward expanding the bellows 73. This downward movement of the push-rod structure 71 is delayed because the rate of expansion of the bellows 73 is determined by the rate at which the air is sucked into the bellows chamber 99 through the adjustable fluid flow passage that comprises that length of the spiral groove 113 that is, at any particular time, covered by the generally even and smooth surface 115 of the flexible member 117. The member 117, when not compressed, is in the general shape of a segment of a sphere or of a parabola. As is best seen in FIG. 3, as the bellows 73 expands, fluid, or air in this instance, is sucked from the chamber 95, through the passage 101, the passage 103, the chamber 97, that part of the spiral groove 113 that is covered by the surface 115 of the flexible member 117, the passage 109, the passage 107, the passages 105 and into the bellows chamber 99.

The push-rod structure 71 moves to a position wherein the shoulder 77 (FIG. 2) thereon engages the free ends 135 of the bell-crank latches 89 to rotate the bell-crank latches 89 about the pins 91 to thereby unlatch the inner contact carrier 41, whereupon the springs 87 (FIG. 1) expand to move the inner contact carrier 41, and the two inner bridging contact members 37 that are carried by the inner contact carrier 41, down to the open position. Thus, the actuation of the two inner (FIG. 2) pole units is delayed by the time delay mechanism 9.

After operation of the inner contact carrier 41, and when the coil 21 is deenergized, the armature 27 is moved back up to the position seen in FIGS. 1 and 2 by means of two springs 137 (only one of which is shown in FIG. 2). The springs 137 and 35 are stronger than the springs 87 (FIG. 1) and 83 so that as the armature 27 moves up moving the outer contact carrier 29 which is attached to the armature upward, the contact carrier 29 engages a portion of the inner contact carrier 41 to force the inner contact carrier up to the position seen in FIGS. 1 and 2 charging the springs 87 (FIG. 1). As the armature 27 is moved upward, it engages the push-rod structure 71 to move the push-rod structure 71 upward charging the spring 33. When the inner contact carrier 41 reaches the position seen in FIGS. 1 and 2, it is again latched by means of the bell-crank type latches 89 that are biased to the latching position by torsion springs (not shown).

As the push-rod structure 71 is moved to the upper position seen in FIGS. 1 and 2, the valve 79 is moved away from the valve seat 74 of the bellows valve 73, and the spring 85 operates to collapse the valve 73 until the valve seat 74 is again seated against the valve 79 in the upper position. The valve 73 can be collapsed under the force of the relatively weak spring 85, because as the push-rod structure 71 moves upward moving the valve 79 upward, the air can freely pass past the valve seat 74 from inside the chamber 95 (FIG. 3) and into the bellows chamber 99.

As was previously described, the rate of fluid flow into the bellows chamber 99 and, therefore, the length of time delay of the actuation of the inner contact carrier 41 is determined by the length of the spiral groove 113 that is covered by the surface 115 of the flexible member 117. This length is adjustable by rotation of the handle 125 to thereby operate the adjusting structure 69. As can be seen in FIG. 3, the member 123 has a threaded portion 139 that cooperates with internal threads 141 in a tapped opening in the member 56, so that rotation of the handle 125 will move the adjusting structure axially up or down. As the adjusting structure 69 is varied in height by this adjustment, the amount of compression on the flexible member 117 is varied so that more or less length of the spiral groove 113 is covered by the surface 115. For example, if the handle 125 is rotated to move the member 117 downward, the part of this member that engages the plate 111 will flatten out to increase the length of the spiral adjustable fluid flow passage. The smooth outer surface or skin 115 of the member 117 is tough enough that it will not protrude down appreciably into the groove 113 of the member 111. As was previously described, the stem 121 is positioned in the opening in the member 123 without being rigidly secured to the member 123. During adjustment, rotation andaxial movement of the member 123 moves the members 121, 119, 117 rectilinearly toward and away from the member 111 without rotating the members 121, 119, 117. Thus, there is no twisting action of the flexible member 117 against the plate 111 during adjustment of the device. Downward (FIG. 3) movement of the member 123 biases the structure 121, 119, 117 downward to flex the member 117 and flatten the surface 115 thereof against the plate 111 to thereby cover more of the groove 113 and increase the working length of the flow passage. Thereafter, when the member 123 is moved upward, the resiliency of the charged flexible member 117 moves the structure 121, 119, 117 upward to uncover more of the groove 113 and decrease the working length of the flow passage.

Operation of the adjusting structure 69 provides a substantially linear adjustment characteristic that is advantageous in an adjustable time delay mechanism. Thus, the time delay in seconds, in relation to the number of turns of adjustment of the structure 69 will be graphed as a substantially straight line. As the spiral fluid flow passage is lengthened, the time delay is lengthened and, as the spiral fluid flow passage is shortened the time delay is shortened. The time delay of the control device 5 is constructed to be adjustable from a time delay of zero seconds to an upper time delay of approximately 60 seconds.

Another embodiment of the invention is seen in FIG. 5 wherein those parts that are identical to the parts seen in FIG. 3 are designated by the same reference characters that are seen in FIG. 3. As can be seen in FIG. 5, a plate 143 that is a generally circular disk-shaped member is provided with a flat generally smooth surface 145, and a flexible adjusting member 147, that is shaped generally as a segment of a sphere, is provided with a spiral groove 149 on a generally smooth outer surface 151. The member 147 is hollow and the outer surface 151 is tough enough that the groove 149 will not be distorted when the member 147 is flattened against the member 143. The adjusting structure 69 of FIG. 5 operates generally in the same manner as the adjusting structure 69 of FIG. 3 to vary the time delay by varying the working length of the spiral groove 49. For example, as the member 147 is moved downward (FIG. 5) the area of surface 151 thereof that engages the flat face 145 of the member 143 is increased to cover a greater length of the groove 149 to thereby increase the working length of the spiral fluid flow path.

Another embodiment of the invention is illustrated in FIG. 6 wherein the structure shown is the same as that disclosed in FIG. 5 except that the member 147' is a rigid member having the spiral groove 149 therein and the member 143' is a flexible smooth surfaced diaphragm that flexes according to adjustment of the handle 125 (FIG. 3) to cover various lengths of the spiral groove to thereby provide a longer or shorter working spiral fluid flow path that operates to effect a time delay in the same manner hereinbefore described. The diaphragm 143' has a ring member 144' secured thereto to provide an opening 109' that will not be distorted when the diaphragm is flexed.

Another embodiment of the invention is disclosed in FIG. 7 wherein those parts that are similar to the parts described with reference to FIGS. 1-3 are designated with reference characters identical to those used in FIGS. l-3. An adjusting structure 151 comprises a handle 153 that is suitably secured to a cylindrical shaft 155 that is provided with an opening 156 for receiving the upper part 81 of the adjusting structure 71. The shaft 155 is provided with a male threaded portion 157 that cooperates with a female threaded bore 159 formed in the block 55 to provide rotation and axial movement of the adjusting structure 151 upon rotation of the handle 153. The block 55 is also provided with a cylindrical smooth surfaced internal bore 161 that cooperates with a helical groove 163 on the cylindrical outer surface of the shaft 155 to provide an adjustable fluid flow passage. The fluid flow or air passage extends from the chamber 95, through two passages 165 formed in the block 55, through the working helical fluid flow passage that comprises that part of the helical groove 163 that is covered by the smooth surface of the bore 161, and into the bellows chamber 99. A passage 166 in the member 55 connects the passage 165 to the outer atmosphere through the filter 61. As is seen in FIG. 7, the member 155 is in the lower-most position to thereby cover a maxi mum length of the helical groove 163 with the smooth surface of the bore 161 to thereby provide for a maximum working length of the adjustable helical fluid flow passage. Thus, the structure is adjusted for a maximum time delay. If the handle 153 is rotated to move the adjusting structure 151 upward, the helical groove 163 will move upward whereupon less length of the groove 163 will be covered by the smooth surface of the bore 161 to shorten the working length of the helical fluid flow path and thereby shorten the length of time delay that will be effected by the time delay mechanism 9. The external surface of the shaft 155 that cooperates with the internal bore 161 is also smooth except for the spiral groove 163 and it is constructed to fit with interference in the bore 161 to thereby more effectively seal the wall portions of the working fluid flow path. In order to provide an effective seal the shaft 155 can be constructed of silicone rubber and the block 55 with the internal bore 161 machined therein can be a suitable metallic member.

A further embodiment of the invention is disclosed in FIG. 8 wherein those parts that are similar to the parts of FIG. 7 are designated with reference characters that are the same as those used in FIG. 7. In this structure, the shaft 155 is provided with a silicone rubber sleeve 171 that is suitably secured to the shaft 155 and that comprises a smooth outer cylindrical surface 173. The block 55 is provided with a generally smooth bore 1'75 having a helical groove 177 machined therein. Upon axial adjustment of the shaft 155, the sleeve 171 is moved axially to cover more or less length of the helical groove 177 with the smooth surface 173 of the sleeve 171 to vary the working length of the helical groove 1'77 and thereby vary the amount of time delay effected during operation of time delay mechanism in the same general manner hereinbefore described, The sleeve 171 is provided to fit within the bore 177 with interference in order to effectively seal the Working helical adjustable fluid flow path of the time delay apparatus.

From the foregoing, it can be understood that there r is provided by this invention an improved control device comprising an improved time delay mechanism having a novel fluid flow passage that is adjustable to vary a time-delay function. The working length of the flow passage comprises the length of a multi-turn groove in one member that is covered by the generally smooth surface of another member. Rotation of a threadedly supported adjustor axially moves one of the members to vary the Working length of the flow passage to thereby adjust the length of time delay.

Since numerous changes may be made in the abovedescribed construction, and different embodiments of the invention may be made Without departing from the spirit and scope thereof, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. A time delay mechanism comprising a movable member, a first member having a first surface and an elongated groove therein at said first surface, a second member having a second and generally smooth surface engaging said first surface and overlying at least a part of said elongated groove to form a fluid flow passage, means operable to force fluid through said flow passage, said movable member being movable at a speed controlled by the rate of flow of fluid through said passage, and means adjustable to a stationary position to vary the effective length of said fluid flow passage to thereby vary the rate of flow of fluid through said flow passage.

2. A time delay mechanism comprising a first member having a first surface and a groove therein at said first surface, said groove comprising a plurality of turns, a second member having a second and generally even surface covering at least a part of said groove to form a Working fluid flow passage the length of which is determined by the covered length of said groove, means operable to force fluid through said passage to effect a time delay, and means adjustable to a stationary position to vary the amount of said covering to vary the length of said working fluid flow passage to thereby vary the length of said time delay.

3. A time delay mechanism comprising a first member having a first surface and a groove therein at said first surface, said groove comprising a plurality of turns, a second member having a second and generally even surface, said second surface engaging said first surface and covering at least a part of said groove to form a fluid flow passage the length of which is determined by the covered length of said groove, a movable structure, means operable to force fluid through said flow passage, said movable structure being movable at a speed determined by the flow of fluid through said flow passage, and adjusting means comprising a threadedly supported adjusting member rotatable to vary the amount of said covering to thereby vary the speed of movement of said movable member.

4-. A time delay mechanism comprising a movable member, a spiral fluid flow passage, means operable to force fluid through said spiral flow passage, means controlling the speed of movement of said movable member in accordance with the flow of fluid through said spiral flow passage, and manually adjustable means operable to vary the length of said spiral flow passage to adjust the flow of fluid through said spiral flow passage to thereby adjust the speed of movement of said movable member.

5. A time delay mechanism comprising a movable memher, a first member having a first surface and a spiral groove therein at said first surface, a second member having a second surface engaging said first surface and covering a part of said groove to form a spiral fluid flow passage the length of which is determined by the covered length of said spiral groove, means operable to force fluid through said spiral flow passage, the speed of movement of said movable member being determined by the length of said spiral flow passage, and adjusting means operable to an adjusted position to vary the amount of said covering to thereby vary the speed of movement of said movable member.

6. A time delay mechanism comprising a movable member, a first member having a first surface and a spiral groove therein at said first surface, a second member having a second and generally smooth surface, said second surface engaging said first surface and being in an overlying relationship With at least a part of said groove to form a spiral fluid flow passage the length of which is determined by the amount of said overlying relationship, means operable to force fluid through said flow passage, said movable member being movable at a speed determined by the flow of fluid through said spiral flow passage, and adjusting means comprising a threadedly supported adjusting member rotatable to vary the amount of said overlying relationship to thereby adjust the speed of movement of said movable member.

7. A time delay mechanism comprising a first and movable member, a plate having a first and generally flat sur face, said plate having a groove therein at said flat surface, a second member of flexible material and having a second surface, said second surface being biased against said first surface and covering at least a part of said groove to form a fluid flow passage, means operable to force fluid through said passage, said movable member being movable at a speed determined by the rate movement of fluid through said passage, adjusting means operable to move said second member relative to said first member to vary said bias to thereby vary the amount of said covering and therefore the length of said flow passage, the rate of movement of fluid through said flow passage being determined by the length of said flow passage.

8. A time delay mechanism comprising a movable member, a rigid plate member having a first and generally flat surface, said plate member having a spiral groove therein at said first surface, a flexible member, means biasing said flexible member into engagement with said first surface to cover at least part of the length of said groove to thereby form a fluid flow passage the length of which passage is determined by the amount of said cover, adjustable means operable to increase and decrease the amount of said bias to thereby vary the amount of said covering to vary the length of said spiral fluid flow passage, means operable to force fluid through said flow passage, the rate of flow of fluid through said flow passage being determined by the length of said flow passage, and said movable member being movable at a speed determined by the rate of flow of fluid through said passage.

9. A time delay mechanism comprising a movable memher, a first member having a first generally flat and planar surface, a flexible member having a second surface and an annular groove therein at said second surface, means biasing said flexible member into engagement with said planar surface to cover a part of said groove to thereby form a fluid flow passage, means operable to force fluid through said flow passage, said movable member being movable in accordance with the rate of fluid flowing through said flow passage, the rate of fluid flowing through said flow passage being determined by the length of said flow passage, and means adjustable to vary said bias to 9 vary the amount of said cover to thereby vary the length of said flow passage.

10. A time delay mechanism comprising a movable member, a first and generally rigid member having a generally flat and generally smooth first surface, a flexible member having a second surface and an annular groove therein at said second surface, said annular groove comprising a plurality of turns, means biasing said flexible member against said first member to cover a length of said groove with said second surface, the covered length of said groove comprising a fluid flow passage, adjusting means comprising threadedly supported adjusting member rotatable to vary said bias to thereby vary the length of said flow passage, means operable to force fluid through said flow passage, and said movable member being movable at a speed determined by the flow of fluid through said flow passage.

It. In a time delay mechanism a first member comprising a flexible diaphragm having a generally smooth first surface which first surface is generally flat when said diaphragm is in an unbiased condition, a second and generally rigid member having a second and curved surface, said second member having a groove therein at said second surface, means biasing said second surface against said first surface to cover a length of said groove to form a fluid flow passage the length of which is determined by the covered length of said groove, and means operable to force fluid through said flow passage to effect a time delay.

12. A time delay mechanism comprising a movable member, a first member comprising a flexible diaphragm having a generally smooth first surface which first surface is generally flat when said diaphragm is in an unbiased condition, a second and generally rigid member having a second and curved surface, said second member having a groove therein at said second surface, said groove comprising a plurality of turns, means biasing said second surface against said first surface to cover a length of said groove to form a fluid flow passage the length of which is determined by the covered length of said groove, means operable to force fluid through said flow passage, said movable member being movable at a speed determined by the length of said flow passage, and means operable to adjust the amount of said bias to adjust the length of said flow passage to thereby adjust the speed of movement of said movable member.

113. A time delay mechanism comprising a movable member, a first member comprising a flexible diaphragm having a generally smooth first surface which first surface is generally flat when said diaphragm is in an unbiased condition, a second and generally rigid member having a second and curved surface, said second member having a spiral groove therein at said second surface, means biasing said second surface against said first surface to cover a length of said groove to form a fluid flow passage the length of which is determined by the covered length of said groove, means operable to force fluid through said flow passage, said movable member being movable at a speed determined by the length of said flow passage, and means operable to adjust the length of said flow passage to thereby adjust the amount of said bias to adjust the speed of movement of said movable member.

14. A time delay mechanism comprising a movable member, a first member having an opening therein and a generally cylindrical internal first surface at said opening, a second member having a second and generally cylindrical external surface, said second member being disposed at least partially within said opening with said second surface engaging said first surface, one of said first and second surfaces being generally smooth, the other of said first and second surfaces being grooved which groove is covered at least partially by said one surface to form a fluid flow passage the length of which is determined by the amount of said covering, and means operable to various stationary adjusted positions to adjust the amount of said covering to adjust the length of said flow passage, means operable to force fluid through said flow passage and to move said movable member at a speed determined by the length of said flow passage.

15. A time delay mechanism comprising a movable member, a first member having an opening therein and a first internal cylindrical surface within said opening, a second member having a cylindrical external surface disposed at least partially within said opening, at least one of said surfaces being smooth, the other of said surfaces having a helical groove therein, said surfaces engaging to cover a length of said groove to form a helical fluid flow passage the length of which is determined by the covered length of said groove, threaded supporting means rotatable to axially move said second cylindrical member as a unit within said opening to vary the amount of said cover to thereby vary the length of said fluid flow passage, means operable to force fluid through said flow passage at a rate of flow determined by the length of said flow passage, and said movable member being movable at a speed determined by the rate of fluid flow through said flow passage.

16. A time delay mechanism comprising a movable member, a first member having an opening therein and an internal generally cylindrical first surface within said opening, a second member having an external cylindrical second surface and a helical groove therein at said cylindrical second surface, means supporting said second member within said opening such that said first surface engages said second surface to cover a length of said helical groove to form a helical fluid flow passage, adjusting means operable to move one of said first and second members axially relative to the other to various adjusted positions to thereby adjust the length of said helical flow passage, means operable to force fluid through said helical fluid flow passage, and said movable member being movable at a speed determined by the rate of flow of fluid through said flow passage to effect a time delay.

17. A time delay mechanism comprising a movable member, a first member having an opening therein and a first generally smooth internal cylindrical surface at said opening, a second member having an external cylindrical second surface, said second member having a helical groove therein at said second surface, means supporting said second member within said opening such that said first surface engages said second surface to cover a length of said helical groove to form a helical fluid flow path the length of which is determined by the covered length 0f sai d groove, adjusting means comprising a threaded ad usting structure rotatable to move said second member axially to vary the amount of cover of said helical groove means operable to force fluid through said fluid flow pas sage, and said movable member being movable in accordance with the rate flow of fluid through said fluid flow passage to effect a time delay.

18. A time delay mechanism comprising a movable member, a first member having an internal cylindrical first surface and a helical groove therein at said first surface, a second member having an external cylindrical second surface, said external cylindrical second surface being generally smooth, said second surface engaging said first surface to cover a length of said groove to form a helical fluid flow passage the length of which is determined by the amount of said covering, means operable to force fluid through said fluid flow passage, said movable member being movable to effect a time delay in accordance with the rate of flow of fluid through said passage, and ad usting means operable to move said second member axially to various stationary adjusted positions to vary the amount of said covering to thereby vary the rate of flow of fluid through said fluid flow passage.

19. A time delay mechanism comprising a movable member, a first member having an internal cylindrical first surface and a helical groove therein at said first sur face, a second member having an external cylindrical second surface, said second surface being generally smooth, said second surface engaging said first surface to cover a length of said groove to thereby form a helical fluid flow passage the length of which is determined by the amount of said covering, adjusting means comprising a threadedly supported adjusting member, upon rotation of said adjusting member said second member moving axially to vary the amount of said covering to thereby vary the length of said helical fluid flow passage, means operable to force fluid through said flow passage, and said movable member being movable at a speed determined by the rate of flow of fluid through said helical fluid flow passage.

20. A control device comprising a control structure and a time delay apparatus, said control structure comprising a coil, a magnetic member, an armature movable relative to said magnetic member, a stationary contact structure, a movable contact structure cooperable with said stationary contact structure to open and close an electric circuit, upon the occurrence of a change in the electrical condition of said coil said armature being actuated to move, said time delay apparatus comprising means latching said movable contact structure in a first operating position, a movable structure actuated to move upon actuation of said armature, control means comprising a first member having a first surface and a groove therein at said first surface, said groove comprising a plurality of turns, a second member having a second and generally even surface covering a length of said groove to form a fluid flow passage the length of which is determined by the covered length of said groove, the speed of movement of said movable member being determined by the rate of movement of fluid flow through said flow passage, the rate of movement of fluid through said flow passage being determined by the length of said flow passage, means adjustable to vary the amount of said covering to thereby vary the length of said flow passage, means unlatching said latching means when said movable member reaches a predetermined position, and means operating when said unlatching means is unlatched to effect movement of said movable contact structure from said first operating position to a second operating position.

21. A control device comprising, in combination, a control structure and a time delay apparatus, said control structure comprising a coil, a magnetic member, an armature movable relative to said magnetic member, a stationary contact structure, a movable contact structure cooperable with said stationary contact structure to open and close an electric circuit, upon the occurrence of a change in the electrical condition of said coil said armature being actuated to move, said time delay apparatus comprising means latching said movable contact structure in a first operating position, a first member having a first surface and a groove therein at said first surface, said groove comprising a plurality of turns, a second member having a second and generally smooth surface covering a length of said groove to form a fluid flow passage the length of which is determined by the covered length of said groove, threaded adjusting means rotatable to vary the amount of said covering to thereby vary the length of said fluid flow passage, the speed of movement of said movable member being determined by the rate of flow of fluid through said fluid flow passage, the length of said fluid flow passage determining the rate of flow of fluid through said fluid flow passage, means unlatching said latching means when said movable member reaches its predetermined position, and means operating when said unlatching means is unlatched to effect movement of said movable contact structure from said first operating position to a second operating position.

22. A control device comprising a control structure and a time delay mechanism, said control structure comprising a coil, a magnetic member, an armature movable relative to said magnetic member, a stationary contact structure, a movable contact structure cooperable with said stationary contact structure to open and close an electric circuit, upon the occurrence of a change in the electrical condition of said coil said armature being actuated to move relative to said magnetic member, said time delay apparatus comprising means latching said movable contact structure in a first operating position, a movable member actuated to move upon actuation of said armature, control means comprising a first and generally rigid member having a generally fiat first surface and a spiral groove therein at said first surface, a flexible member having a second surface adapted to engage said first surface to cover a length of said spiral groove to form a spiral fluid flow passage, adjusting means comprising a threadedly supported adjusting member rotatable to flex said flexible member to vary the engagement of said second surface against said first surface to thereby vary the length of said spiral fluid flow passage, the speed of movement of said movable member being determined by the rate of movement of fluid flow through said passage, the rate of fluid flow through said passage being determined by the length of said passage, said movable member being operable to unlatch said latching means when said movable member has moved a predetermined distance, and means operable when said latching means is unlatched to move said movable contact structure from said first operating position to a second operating position.

References Cited by the Examiner UNITED STATES PATENTS 942,623 12/09 Dixon 200-34 2,506,152 5/50 Hunter 13843 X 2,511,733 6/50 Morrison 13843 2,521,202 9/50 Cloudsley 18888 2,735,515 2/56 Cloudsley 18888 FOREIGN PATENTS 1,225,091 2/60 France.

JOHN F. BURNS, Primary Examiner.

LARAMIE E. ASKIN, Examiner, 

1. A TIME DELAY MECHANISM COMPRISING A MOVABLE MEMBER, A FIRST MEMBER HAVING A FIRST SURFACE AND AN ELONGAGED GROOVE THEREIN AT SAID FIRST SURFACE, A SECOND MEMBER HAVING A SECOND AND GENERALLY SMOOTH SURFACE ENGAGING SAID FIRST SURFACE AND OVERLYING AT LEAST A PART OF SAID ELONGATED GROOVE TO FORM A FLUID FLOW PASSAGE, MEANS OPERABLE TO FORCE FLUID THROUGH SAID FLOW PASSAGE, SAID MOVABLE MEMBER BEING MOVABLE AT A SPEED CONTROLLED BY THE RATE OF FLOW OF FLUID THROUGH SAID PASSAGE, AND MEANS ADJUSTABLE TO A STATIONARY POSITION TO VARY THE EFFECTIVE LENGTH OF SAID FLUID FLOW PASSAGE TO THEREBY VARY THE RATE OF FLOW OF FLUID THROUGH SAID FLOW PASSAGE. 